(1) Field of the Invention
This invention relates to a process for preparing a cinnamate ester by reacting carbon monoxide, oxygen, and its corresponding styrene compound and alcohol.
(2) Description of the Prior Art
Cinnamate esters have found wide-spread commercial utility as perfumes, fragrant materials, flavors and the like and raw materials therefor owing to their inherent aroma. They are also important as raw materials for agricultural chemicals and photosensitive resins.
Cinnamic acid has conventionally been produced on small scales by using benzaldehyde and derivatives of acetic acid as principal raw materials. This process is however not preferred from the industrial viewpoint since it requires such costly raw materials.
As processes permitting use of more economical raw materials, it has also been proposed to prepare a cinnamate ester by reacting carbon monoxide, oxygen and its corresponding styrene compound and alcohol in the presence of a catalyst (see, for example, Japanese Patent Laid-Open Nos. 15242/1981 and 70836/1982).
In these processes, the activities of the catalysts are however still low and their reaction results are not fully satisfactory. For these reasons, they have not yet been practiced on any industrial scales.